Continuous production system for chlorosulfonated polyethylene

Abstract

The utility model belongs to the technical field of high polymer material production equipment, and relates to a chlorosulfonated polyethylene continuous production system. A liquid phase outlet end at the bottom of a first dissolving pre-chlorination kettle is connected with a first liquid phase inlet end at the top of a second dissolving pre-chlorination kettle; a liquid phase outlet end at the bottom of the second dissolving pre-chlorination kettle is connected with a liquid phase inlet end at the top of a glue solution intermediate tank, a first liquid phase outlet end at the bottom of the glue solution intermediate tank is connected with a liquid phase inlet end of a glue solution pump, and a liquid phase outlet end of the glue solution pump is connected with a liquid phase inlet end of a first condensation kettle; the outlet end of the first condensation kettle is connected with the inlet end of the second condensation kettle, and the outlet end of the second condensation kettle is connected with the extrusion forming granulation unit; a second liquid phase outlet end at the top of the glue solution intermediate tank is connected with an inlet end of the acid gas absorption tower, an outlet end of the acid gas absorption tower is connected with an inlet end of the demister, and an outlet end of the demister is connected with the tail gas boundary area. And the product quality and the production efficiency are effectively improved.

Description

Technical Field

[0001] This utility model belongs to the technical field of polymer material production equipment, and in particular to a continuous production system for chlorosulfonated polyethylene. Background Technology

[0002] Chlorosulfonated polyethylene, as a high-performance specialty rubber, faces the following technical bottlenecks in its traditional production process:

[0003] Low solvent recovery rate: The prechlorination and chlorosulfonation reactions use large amounts of volatile raw materials such as carbon tetrachloride and chlorine. Existing equipment mostly uses a single condenser or direct emission, resulting in solvent loss of up to 20%-30%, and the cost of waste gas treatment is high. Limitations of intermittent production: Relying on single-reactor intermittent operation, material transfer requires frequent start-ups and shutdowns of equipment, resulting in long production cycles (≥8 hours / batch) and equipment utilization of less than 60%, which is difficult to meet the needs of large-scale production. Impurity residue problem: The coagulation section lacks a staged removal design, and unreacted sulfur dioxide, free chlorine and other acidic gases are easy to remain in the glue solution, resulting in excessive sulfur content in the finished product (≥0.05%), affecting aging resistance. Poor granulation uniformity: Traditional single-stage extruders do not completely remove devolatilization. Air bubbles and undispersed additives in the glue solution result in rough particle surfaces and high agglomeration rate, requiring an additional screening and rework process.

[0004] Chinese Patent Publication No. CN205528548U discloses an improved chlorosulfonated polyethylene production system. The reactor lid is equipped with solvent and initiator feed pipes with feed valve I; a feed pipe inserted into the bottom of the reactor has sulfur dioxide feed valve VII and chlorine feed valve VIII; a polyethylene and terminator feed pipe has feed valve III; and a charging pipe has nitrogen charging valve IV. A steam-jacketed reactor is connected at its top to the side inlet of a condenser I, whose side outlet is connected to the top of the reactor. The condenser outlet is connected to an existing treatment facility via pipeline valve II. A hot water pump inlet is connected to a hot water tank, and a hot water pump outlet valve VI is connected to a condensation reactor. The outlet of the hot water pump outlet valve VI is connected to the bottom of the reactor with outlet valve V via a pre-exit pipe. The side outlet of the condensation reactor is connected to the hot water pump inlet pipeline via a vibrating screen and a hot water tank. The top of the condensation reactor is connected to the side inlet of a condenser II, and the side outlet of condenser II is connected to a recovery tank. The vibrating screen is connected to a single-screw extruder.

[0005] Although this invention attempts to improve efficiency by modifying the reactor structure, it still fails to resolve the contradiction between continuous production and impurity control, and the mixing uniformity of the granulation system has not been fundamentally improved. Therefore, there is an urgent need for a production system that integrates efficient solvent recovery, continuous reaction, and multi-stage purification to overcome the aforementioned technical obstacles. Utility Model Content

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a continuous production system for chlorosulfonated polyethylene to solve the problems of uneven reaction, fluctuation in adhesive delivery, impurity residue and waste gas emission in the existing production process.

[0007] The technical problem solved by this utility model is achieved through the following technical solution:

[0008] A continuous production system for chlorosulfonated polyethylene includes a first dissolving prechlorination kettle, a second dissolving prechlorination kettle, an intermediate glue tank, a glue pump, a first condensation kettle, a second condensation kettle, an acid gas absorption tower, a demister, and an extrusion molding and granulation unit. The liquid phase outlet at the bottom of the first dissolving prechlorination kettle is connected to the first liquid phase inlet at the top of the second dissolving prechlorination kettle. The liquid phase outlet at the bottom of the second dissolving prechlorination kettle is connected to the liquid phase inlet at the top of the intermediate glue tank. The first liquid phase outlet at the bottom of the intermediate glue tank is connected to the liquid phase inlet of the glue pump. The liquid phase outlet of the glue pump is connected to the liquid phase inlet of the first condensation kettle. The outlet of the first condensation kettle is connected to the inlet of the second condensation kettle. The outlet of the second condensation kettle is connected to the extrusion molding and granulation unit.

[0009] The second liquid phase outlet at the top of the intermediate tank is connected to the inlet of the acid gas absorption tower, the outlet of the acid gas absorption tower is connected to the inlet of the demister, and the outlet of the demister is connected to the tail gas boundary.

[0010] Furthermore, the extrusion molding granulation unit includes a large vibrating screen, a washing tank, a small vibrating screen, a primary extruder, a secondary extruder, a fluidized bed, an elevator, and a packaging scale. The outlet end of the large vibrating screen is connected to the inlet end of the washing tank, the outlet end of the washing tank is connected to the inlet end of the small vibrating screen, the outlet end of the small vibrating screen is connected to the inlet end of the primary extruder, the outlet end of the primary extruder is connected to the inlet end of the secondary extruder, the outlet end of the secondary extruder is connected to the inlet end of the fluidized bed, the outlet end of the fluidized bed is connected to the inlet end of the elevator, and the outlet end of the elevator is connected to the packaging scale.

[0011] Furthermore, it also includes a first condenser, wherein the gas phase outlet end of the top of the first dissolving prechlorination vessel is connected to the gas phase inlet end of the first condenser, the liquid phase outlet end of the first condenser is connected to the liquid phase inlet end of the top of the first dissolving prechlorination vessel, and the gas phase outlet end of the first condenser is connected to the tail gas boundary area.

[0012] Furthermore, it also includes a second condenser, wherein the gas phase outlet end of the top of the second dissolving prechlorination vessel is connected to the gas phase inlet end of the second condenser, the liquid phase outlet end of the second condenser is connected to the second liquid phase inlet end of the top of the second dissolving prechlorination vessel, and the gas phase outlet end of the second condenser is connected to the tail gas boundary area.

[0013] Furthermore, a gas distributor is installed at the bottom of the intermediate tank for the adhesive.

[0014] Furthermore, a stirring device is installed at the top of the intermediate tank of adhesive liquid, and the blades of the stirring device are propeller-type.

[0015] Furthermore, several reagent addition ports are evenly arranged on the tank wall along the height of the tank body. Each reagent addition port is equipped with a short tube that is tightly connected to the tank body. The short tube is welded perpendicularly to the tank wall. The outlet end of the short tube is connected to the inlet end of the metering pump, and the outlet end of the metering pump is connected to the stabilizer storage tank.

[0016] The advantages and positive effects of this utility model are:

[0017] 1. This utility model uses a first condenser and a second condenser to condense the gas phase generated in the first and second dissolution prechlorination kettles, respectively, so as to effectively recover the unreacted carbon tetrachloride vapor and return the liquid carbon tetrachloride to the corresponding dissolution prechlorination kettle to continue to participate in the reaction. This greatly reduces solvent loss, lowers production costs, and also reduces waste gas emissions and waste gas treatment costs.

[0018] 2. This utility model adopts a first dissolving prechlorination kettle and a second dissolving prechlorination kettle connected in series, as well as continuous pipeline connections between each piece of equipment. Materials can be transferred continuously without frequent start-ups and shutdowns, which shortens the production cycle, improves equipment utilization, and can meet the needs of large-scale production.

[0019] 3. This utility model sets up a gas distributor in the intermediate tank of the adhesive solution, combined with an acid gas absorption tower and a demister, which can effectively remove acidic gas impurities from the adhesive solution and reduce the sulfur content in the finished product. Compared with the traditional deacidification method, the removal rate of acidic gas is increased by 20%-30%, which effectively reduces the residual acidic impurities in the product and improves the purity and stability of the product.

[0020] 4. This utility model effectively solves the problem of incomplete devolatilization in traditional single-stage extruders by using a two-stage extrusion process with a first-stage and a second-stage extruder. It reduces air bubbles and undispersed additives in the adhesive, lowers the surface roughness and agglomeration rate of the particles, eliminates the need for additional screening and rework processes, and improves product quality and production efficiency.

[0021] 5. The design of the gas distributor, stirring device, and reagent addition port in this invention not only considers the realization of functions but also takes into account the convenience of equipment maintenance. This greatly reduces equipment maintenance costs and downtime, and improves the continuity and stability of production. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of this utility model.

[0023] Figure Labels

[0024] 1-First condenser, 2-Second condenser, 3-Acid gas absorption tower, 4-Demister, 5-First condensation vessel, 6-Second condensation vessel, 7-Large vibrating screen, 8-Glue washing tank, 9-Small vibrating screen, 10-First stage extruder, 11-Second stage extruder, 12-Fluidized bed, 13-Elevator, 14-Packaging scale, 15-Metering pump, 16-Glue pump, 17-Stirring device, 18-Glue intermediate tank, 19-Second dissolving and prechlorination vessel, 20-First dissolving and prechlorination vessel. Detailed Implementation

[0025] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The following embodiments are only descriptive and not limiting, and should not be used to limit the protection scope of the present invention.

[0026] A continuous production system for chlorosulfonated polyethylene includes a first dissolving prechlorination vessel 20, a second dissolving prechlorination vessel 19, an intermediate adhesive tank 18, an adhesive pump 16, a first condensation vessel 5, a second condensation vessel 6, an acid gas absorption tower 3, a demister 4, and an extrusion molding granulation unit. The liquid phase outlet at the bottom of the first dissolving prechlorination vessel 20 is connected to the first liquid phase inlet at the top of the second dissolving prechlorination vessel 19. The liquid phase outlet at the bottom of the second dissolving prechlorination vessel 19 is connected to the liquid phase inlet at the top of the intermediate adhesive tank 18. The first liquid phase outlet at the bottom of the intermediate adhesive tank 18 is connected to the liquid phase inlet of the adhesive pump 16. The liquid phase outlet at the adhesive pump 16 is connected to the liquid phase inlet of the first condensation vessel 5. The outlet at the first condensation vessel 5 is connected to the inlet at the second condensation vessel 6. The outlet at the second condensation vessel 6 is connected to the extrusion molding granulation unit.

[0027] The second liquid phase outlet at the top of the intermediate tank 18 is connected to the inlet of the acid gas absorption tower 3, the outlet of the acid gas absorption tower 3 is connected to the inlet of the demister 4, and the outlet of the demister 4 is connected to the tail gas boundary.

[0028] The extrusion molding granulation unit includes a large vibrating screen 7, a washing tank 8, a small vibrating screen 9, a first-stage extruder 10, a second-stage extruder 11, a fluidized bed 12, an elevator 13, and a packaging scale 14. The outlet end of the large vibrating screen 7 is connected to the inlet end of the washing tank 8, the outlet end of the washing tank 8 is connected to the inlet end of the small vibrating screen 9, the outlet end of the small vibrating screen 9 is connected to the inlet end of the first-stage extruder 10, the outlet end of the first-stage extruder is connected to the inlet end of the second-stage extruder 11, the outlet end of the second-stage extruder 11 is connected to the inlet end of the fluidized bed 12, the outlet end of the fluidized bed 12 is connected to the inlet end of the elevator 13, and the outlet end of the elevator 13 is connected to the packaging scale 14.

[0029] It also includes a first condenser 1, the gas phase outlet end of the top of the first dissolving prechlorination vessel 20 is connected to the gas phase inlet end of the first condenser 1, the liquid phase outlet end of the first condenser 1 is connected to the liquid phase inlet end of the top of the first dissolving prechlorination vessel 20, and the gas phase outlet end of the first condenser 1 is connected to the tail gas boundary area.

[0030] It also includes a second condenser 2, the gas phase outlet end of the top of the second dissolving prechlorination vessel 19 is connected to the gas phase inlet end of the second condenser 2, the liquid phase outlet end of the second condenser 2 is connected to the second liquid phase inlet end of the top of the second dissolving prechlorination vessel 19, and the gas phase outlet end of the second condenser 2 is connected to the tail gas boundary area.

[0031] A gas distributor is installed at the bottom of the intermediate tank 18 for the adhesive solution.

[0032] A stirring device 17 is installed on the top of the intermediate tank 18 for the adhesive solution. The blades of the stirring device 17 are propeller-type.

[0033] Several reagent addition ports are evenly arranged on the tank wall of the intermediate adhesive tank 18 along the height direction of the tank body. Each reagent addition port is equipped with a short tube that is tightly connected to the tank body. The short tube is welded perpendicularly to the tank wall. The outlet end of the short tube is connected to the inlet end of the metering pump 15. The outlet end of the metering pump 15 is connected to the stabilizer storage tank.

[0034] In this embodiment of the invention, a measured amount of carbon tetrachloride is fed into the first dissolving and prechlorinating reactor 20. Simultaneously, polyethylene is fed into the first dissolving and prechlorinating reactor 20 for prechlorination. After 90 minutes of prechlorination, the polyethylene is discharged into the second dissolving and prechlorinating reactor 19 using a pressure difference. During the prechlorination reaction, a mixed gas containing unreacted carbon tetrachloride vapor, a small amount of hydrogen chloride gas, and the heat generated by the reaction is produced in the first dissolving and prechlorinating reactor 20. This mixed gas is sent to the first condenser 1 for condensation. A portion of the condensed carbon tetrachloride liquid is returned to the first dissolving and prechlorinating reactor 20 to maintain the reaction system and material quantity within the reactor, ensuring the continuity and stability of the reaction. Another portion, containing uncondensed low-boiling-point impurities and a small amount of hydrogen chloride gas, is sent to the boundary area for tail gas absorption to avoid environmental pollution.

[0035] After the material is poured into the second dissolving and prechlorinating reactor 19, liquid sulfur dioxide is continuously and quantitatively mixed with chlorine gas and introduced into the reactor. The mixture is introduced for 30 minutes, and after rapid analysis of the sulfur content by sampling inside the reactor and confirming it meets the standards, the sulfur dioxide supply is stopped. Then, chlorine gas is continuously introduced for approximately 42 minutes, and after analysis of the chlorine content and confirmation of it meets the standards, the chlorine supply is stopped. During this synthesis reaction stage, the second dissolving and prechlorinating reactor 19 will produce a mixed gas containing unreacted carbon tetrachloride vapor, unreacted sulfur dioxide and chlorine gas, and hydrogen chloride generated from the reaction. This mixed gas is sent to the second condenser 2 for condensation. A portion of the condensed liquid carbon tetrachloride is returned to the second dissolving and prechlorinating reactor 19 to provide a continuous solvent environment for the reaction. The remaining portion, containing unreacted sulfur dioxide, chlorine gas, and acidic gases such as hydrogen chloride, is sent to the boundary area for tail gas absorption and neutralized with an alkaline absorbent to ensure that emissions meet standards. The reactor temperature of the second dissolving and prechlorinating reactor 19 is controlled at 70℃, and the reaction pressure is controlled at 0.03 MPaG.

[0036] The rubber solution produced from the second dissolving prechlorination reactor 19 enters the intermediate rubber solution tank 18 for deacidification treatment. A gas distributor (not shown in the figure) is installed at the bottom of the intermediate rubber solution tank 18. This gas distributor has a flat disc structure and is made of high-strength, corrosion-resistant 316L stainless steel, which allows the introduced nitrogen gas to be evenly dispersed in the rubber solution. Multiple layers of structured packing are installed inside the tank. The packing adopts a new type of corrugated structure, which increases the gas-liquid contact area and further enhances the deacidification effect. An acid gas absorption tower 3 is connected to the top of the tank. The absorption tower uses a spray device to evenly spray the alkaline absorbent liquid, allowing it to fully contact and react with the rising acid gas. A demister 4 is connected to the outlet of the absorption tower to prevent absorbent liquid droplets from being discharged with the tail gas. In this embodiment, the alkaline absorbent liquid is a sodium hydroxide solution.

[0037] When the nitrogen supply device is turned on, nitrogen is introduced into the bottom of the intermediate adhesive tank from the gas distributor at a stable flow rate of 5-15 cubic meters per hour. During the nitrogen's ascent, acidic gases (such as hydrogen chloride and sulfur dioxide) in the adhesive are carried out through gas-liquid contact and enter the acid gas absorption tower from the exhaust port at the top of the tank. In the acid gas absorption tower, sodium hydroxide solution is evenly sprayed by a spray device, reacting countercurrently with the acid gas. The absorbed tail gas passes through demister 4 to remove droplets before being discharged to the subsequent tail gas treatment system.

[0038] A stirring device 17 is installed on the top of the intermediate adhesive tank 18. The stirring blades are designed as propellers. Multiple reagent addition ports are set on the tank wall, each equipped with a metering pump 15. The other end of the metering pump 15 is connected to a stabilizer storage tank. The stabilizer storage tank can store stabilizing reagents such as antioxidants and light stabilizers as needed. The addition amount is precisely controlled by the metering pump 15, and the antioxidants, light stabilizers, and other stabilizing reagents are slowly added to the adhesive through the reagent addition port. After the reagents are added, stirring is continued for a period of time to ensure that the reagents and adhesive are fully mixed and reacted, completing the stabilization treatment.

[0039] The treated adhesive solution is pumped sequentially to the first coagulation vessel 5 and the second coagulation vessel 6 at a pressure of 0.3 MPaG. This two-stage coagulation process further enhances the coagulation effect, ensuring the polymer in the adhesive solution is fully coagulated into granules, facilitating subsequent processing and improving product quality stability and consistency. After initial coagulation in the first coagulation vessel 5, the solution undergoes secondary coagulation in the second coagulation vessel 6, allowing for more precise control of the coagulation degree and reducing product quality issues caused by insufficient or excessive coagulation.

[0040] The adhesive solution exiting the second coagulation vessel 6 undergoes preliminary separation of larger particulate impurities or incompletely coagulated lumps via a large vibrating screen 7. Vibration causes the material to move on the screen mesh, allowing solution that conforms to the screen aperture size to pass through, while impurities and large particles are retained. The solution is then washed in a washing tank 8 to remove residual impurities, coagulants, and other substances that may affect product quality. Finally, a small vibrating screen 9 further refines the solution after washing in the washing tank 8, removing smaller impurities and unwashed particles to improve the purity of the solution.

[0041] Then, the adhesive liquid is initially extruded by a first-stage extruder 10 to remove some moisture and solvent, and at the same time, the adhesive liquid is initially shaped to improve its density and strength. Based on the first-stage extrusion, the adhesive liquid is further extruded and plasticized by a second-stage extruder 11 to achieve a more ideal molding state and improve the quality and performance of the product.

[0042] The adhesive solution is then dried in a fluidized bed 12 to remove residual moisture and volatile substances, ensuring the product meets the specified moisture content standard. After drying in the fluidized bed 12, the adhesive solution is lifted to a certain height by an elevator 13 for transport to the subsequent packaging scale 14 for packaging. The adhesive solution, after a series of treatments, is quantitatively weighed and packaged to ensure that the weight of each bag of product meets the specified standard, facilitating storage and transportation.

[0043] Although embodiments and drawings of the present invention have been disclosed for illustrative purposes, those skilled in the art will understand that various substitutions, variations and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A continuous production system for chlorosulfonated polyethylene, characterized in that: The system includes a first dissolving and prechlorinating kettle, a second dissolving and prechlorinating kettle, an intermediate adhesive tank, an adhesive pump, a first condensation kettle, a second condensation kettle, an acid gas absorption tower, a demister, and an extrusion molding and granulation unit. The liquid phase outlet at the bottom of the first dissolving and prechlorinating kettle is connected to the first liquid phase inlet at the top of the second dissolving and prechlorinating kettle. The liquid phase outlet at the bottom of the second dissolving and prechlorinating kettle is connected to the liquid phase inlet at the top of the intermediate adhesive tank. The first liquid phase outlet at the bottom of the intermediate adhesive tank is connected to the liquid phase inlet of the adhesive pump. The liquid phase outlet of the adhesive pump is connected to the liquid phase inlet of the first condensation kettle. The outlet of the first condensation kettle is connected to the inlet of the second condensation kettle. The outlet of the second condensation kettle is connected to the extrusion molding and granulation unit. The second liquid phase outlet at the top of the intermediate tank is connected to the inlet of the acid gas absorption tower, the outlet of the acid gas absorption tower is connected to the inlet of the demister, and the outlet of the demister is connected to the tail gas boundary.

2. The continuous production system for chlorosulfonated polyethylene according to claim 1, characterized in that: The extrusion molding granulation unit includes a large vibrating screen, a washing tank, a small vibrating screen, a primary extruder, a secondary extruder, a fluidized bed, an elevator, and a packaging scale. The outlet end of the large vibrating screen is connected to the inlet end of the washing tank, the outlet end of the washing tank is connected to the inlet end of the small vibrating screen, the outlet end of the small vibrating screen is connected to the inlet end of the primary extruder, the outlet end of the primary extruder is connected to the inlet end of the secondary extruder, the outlet end of the secondary extruder is connected to the inlet end of the fluidized bed, the outlet end of the fluidized bed is connected to the inlet end of the elevator, and the outlet end of the elevator is connected to the packaging scale.

3. The continuous production system for chlorosulfonated polyethylene according to claim 2, characterized in that: It also includes a first condenser, wherein the gas phase outlet end of the top of the first dissolving prechlorination kettle is connected to the gas phase inlet end of the first condenser, the liquid phase outlet end of the first condenser is connected to the liquid phase inlet end of the top of the first dissolving prechlorination kettle, and the gas phase outlet end of the first condenser is connected to the tail gas boundary area.

4. The continuous production system for chlorosulfonated polyethylene according to claim 3, characterized in that: It also includes a second condenser, the gas phase outlet end of the top of the second dissolving prechlorination kettle is connected to the gas phase inlet end of the second condenser, the liquid phase outlet end of the second condenser is connected to the second liquid phase inlet end of the top of the second dissolving prechlorination kettle, and the gas phase outlet end of the second condenser is connected to the tail gas boundary area.

5. The continuous production system for chlorosulfonated polyethylene according to claim 4, characterized in that: A gas distributor is installed at the bottom of the intermediate tank for the adhesive.

6. The continuous production system for chlorosulfonated polyethylene according to claim 5, characterized in that: A stirring device is installed at the top of the intermediate tank of adhesive solution, and the blades of the stirring device are propeller-type.

7. The continuous production system for chlorosulfonated polyethylene according to claim 6, characterized in that: Several reagent addition ports are evenly arranged on the tank wall along the height of the tank. Each reagent addition port is equipped with a short tube that is tightly connected to the tank body. The short tube is welded perpendicularly to the tank wall. The outlet end of the short tube is connected to the inlet end of the metering pump. The outlet end of the metering pump is connected to the stabilizer storage tank.

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